[Task]: fix MqttIO flaky test

[twosom]

What needs to happen?

The recently added MqttIO testReadWithMetadata test is flaky.

here is related context

Issue Priority

Priority: 2 (default / most normal work should be filed as P2)

Issue Components

• Component: Python SDK
• Component: Java SDK
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• Component: IO connector
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[twosom]

.take-issue